Guru's Guide to SQL Server Architecture and Internals, The

Threading Models

COM objects support two primary threading models: single-threaded apartment (STA, also known as “apartment-threaded”) and multithreaded apartment (MTA, also known as “free-threaded”). Don't let the “apartment” concept confuse you or scare you away. The term helps define a conceptual framework that describes the relationships among threads, objects, and processes. It establishes an analogy wherein a process is the equivalent of a building, and the logical container in which COM threads and objects exist within a process is an apartment—that is, a set of rooms within the building. Thus an apartment is simply a logical container within a process. As the analogy suggests, an apartment might contain multiple threads and/or objects, ...